im sorry but this just looks odd to me, he may be looking down but the position of his hand indicates that he is shooting to the top right of the siggy. Your background looks weird and doesnt really match with the siggy. Icon man is too blurry and youve blurred his finger right off.
there isnt really a definite light source in this siggy, and there isnt really and flow or depth either.

I would remove the beam from his chest and just have the hand, but change the direction to the top-left and do some other effects to the background :P

nice attempt though